What type of sentence is made up of two simple sentences joined with a comma and a coordinate conjunction a. compound b. compound-complex c. simple d. conplex

A COMPOUND sentence is a type of sentence made up of two simple sentences joined with a comma and a coordinate conjunction.

Other types of sentence are:
1) Simple sentence = a subject, a verb, and a complete thought
2) Complex sentence = a combination of independent clause and a dependent clause connected by a subordinator
3) Compound-complex sentence = combination of at least one dependent clause and more than one independent clause connected with a conjunction and a subordinator.