Which of the following sentence contains a compound subject A.the man arrived at the restaurant on time B. Johnny loves to play basketball c. The children ran and sang D. The boy and sister went to the library
Answer: D. The boy and sister went to the library.
Explanation: When a subject includes two or more noun phrases, it's called a compound subject. "The boy and the sister" refers to two individuals, both of which are part of the subject.