Question

which of the following choices is a properly formed python variable name, meaning it is both legal in the python language and considered good style? studentname 1ststudentnameudent_name student!name! student_name

Explanation:

In Python, variable names must start with a letter or an underscore, can only contain letters, numbers, and underscores, and should not use special characters (except underscore). Also, following the PEP - 8 style guide, snake_case (using underscores to separate words) is considered good style. "StUdEnTnAmE" uses inconsistent capitalization (not following PEP - 8), "1stStUdEnTnAmEudent_name" starts with a number which is illegal, "student!name!" has illegal special characters (!), while "student_name" meets all the requirements.

Answer:

student_name