Question

visitors to northeast ohio should make time to see the mansfield memorial museum. there, tourists can see elektro, the oldest existing robot. it could speak, sing, and walk, and it was an attraction at the 1939 worlds fair. it was controlled by voice, and it spoke using a record player. it told jokes and blew up balloons. a robot dog, sparko, joined elektro for the 1940 worlds fair. it could bark and sit. the robots were childlike calming entertaining expensive

Explanation:

The text mentions that Elektro could speak, sing, walk, tell jokes, and blow up balloons. Sparko could bark and sit. These actions are related to providing entertainment.

Answer:

C. entertaining