In an overhead valve engine, pushrods connect to A. rocker arm which pivots and opens valves
A length of uninterrupted cable connecting two devices
The answer to your question is,
D) Check their pulse.
((Well, some people say to place your ear over the persons mouth and watch for a rise and fall of the chest-- but that's not an answer nor does that really go with any of the answers provided so..))
-Mabel <3
Answer:
The UML diagram and the story is shown on the first uploaded image
Explanation: