Answer:
Step-by-step explanation:
a. All methods in an interface must be abstract methods.
b. All variables in an interface must be public, static, and final.
c. Interfaces cannot be instantiated. (meaning that they do not have a constructor and cannot be created as a regular object.)
d. Interfaces cannot contain fields, properties, or defined methods. (Everything needs to be abstract)
e. Interfaces are considered to be reference implementation classes
Since no answer options were provided, these keywords all fit the into the sentence and make the sentence true.