Final answer:
The valid username that Joshua can create for the second user named Miguel on a Windows 10 laptop is Miguel2. Option 'c' is also technically correct, but 'd' is the clearest unique identifier.
Step-by-step explanation:
For Joshua, a systems administrator, creating multiple local user accounts on Windows 10 laptops with the same name can be a challenge. When two users have the same name 'Miguel', he must use a unique username for each. According to Windows username conventions, special characters such as '?' and '<>' are not allowed, so options 'a' and 'b' are invalid. The options 'c' MigueL and 'd' Miguel2 are both valid as Windows recognizes case sensitivity for the purpose of displaying usernames but not for logging in, and it allows for numeric characters. Therefore, the correct answer is d) Miguel2.