正解：

Explanation:
First drop-down: datalist
Second drop-down: vehicles
Third drop-down: < /datalist >
The correct element is < datalist > because the interface requires a text input that provides selectable suggestions while still allowing the user to type. The < input > element uses list= " vehicles " , so it must be connected to a < datalist > element whose id is exactly vehicles. The id cannot be vehicle, because vehicle is already the input element's own identifier and does not match the value used by the list attribute. The < option
> elements inside the datalist define the suggested values: Motorcycle, Truck, Boat, Car, and Bicycle. ul, ol, and li are list-markup elements and do not create input suggestions. select would create a fixed dropdown list, but it would not match the editable input-with-suggestions behavior shown. The closing tag must match the opening datalist element, so the final selection is < /datalist > .

正解：

Explanation:
Determine requirements # Develop code # Test the app
#
Monitor performance # Deploy the app
The correct application lifecycle sequence begins with Determine requirements because the team must first define what the app must accomplish, who will use it, and which functional and technical expectations must be satisfied. Since the question states that the design is already provided, the next implementation step is Develop code, where the HTML, CSS, JavaScript, assets, APIs, and app logic are created according to the approved design and requirements. After development, the app must be validated through Test the app.
Testing confirms that the app works correctly, meets requirements, handles user input properly, and does not contain functional defects that would block release. Once testing is complete, the app can be released through Deploy the app, which publishes it to the target environment or makes it available to users. The final operational stage is Monitor performance, where the released app is observed, maintained, updated, and improved based on performance, reliability, defects, and user behavior. References/topics: application lifecycle management, requirements, development, testing, deployment, maintenance.

正解：

Explanation:
pattern # Provides a way to set a regular expression that the value must match placeholder # Provides a way to set default text that displays until focus is placed in an element required # Provides a way to set form elements as mandatory multiple # Provides a way to allow more than one file or email address in a single input The correct matches are based on standard HTML5 form validation and input-attribute behavior. The pattern attribute defines a regular expression that the input value must satisfy before the form can be submitted successfully. It is commonly used for structured values such as phone numbers, codes, postal formats, or custom identifiers. The placeholder attribute supplies short hint text inside an input field, helping the user understand the expected value before entering data. The required attribute makes a form control mandatory; if the field is empty, constraint validation prevents successful submission. The multiple attribute allows a single input to accept more than one value, specifically for controls such as input type= " file " and input type= " email " , where users may upload multiple files or enter multiple email addresses. The maxlength attribute is not used in these matches because it limits the maximum number of characters that can be entered, but none of the listed descriptions asks for character-length restriction. References/topics: HTML5 form attributes, constraint validation, pattern, placeholder, required, multiple, input validation.

正解：B、C  🗳️

解説: (CertShiken メンバーにのみ表示されます)

正解：A、C  🗳️

解説: (CertShiken メンバーにのみ表示されます)