Answer:
A. He holds onto a heavy rock to push himself down.
Explanation:
Jerry is very surprised and curious when he sees the boys diving through the tunnel. He wants to have that same experience, but because he is a foreigner and cannot speak the local language, the boys do not give Jerry the opportunity to join them and learn what they do. So Jerry starts training and planning how the tunnel entrance will arrive on his own and successfully. When putting his plan into practice, Jerry holds on to a very heavy stone, which will help him push himself down.
