By the conduction process the heat reaches the pin.Option C is correct.
What is heat transfer?
The term "heat transfer" refers to the movement of heat. The flow of heat across a system's boundary is due to a temperature differential between the system and its surroundings.
Conduction is the type of heat transfer occurs mainly in solid or by contact.In the given condition the rod is then heated continuously at one end and the pins fall off in the order 4, 3, 2, 1.
By the conduction process the heat reaches the pin.
Hence option C is correct.
To learn more about the heat transfer refer to the link;
https://brainly.com/question/13433948
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