Which one of the following regular expression matches any string containing zero or one p?

A. 1 and 2 B. 2 and 4 C. 1 and 4 D. 2 and 3

A. p+ B. p* C. P? D. p#

A. [A-Za-z0-9] B. [A-za-z] C. [A-z] D. [a-z]

A. 7 B. 8 C. 9 D. 10