Every student can learn rope jumping. You can jump alone or with your classmate. You can also help turn a long rope for many others to jump over, one at a time. If you jump alone, you will need a short rope and it will be just enough for your height. Try ropes of different lengths until you find a right one for your size.  A rope should be turned slowly. It must also be turned high enough to let you jump freely and safely. Turning the rope freely and safely needs careful timing. In rope jumping, timing means turning the rope slowly enough for you to jump over at the right time without its striking your feet. When you jump rope, your heart beats faster and your face has a healthy color1. But if you jump too many times at first, you will get fired. You must learn when to stop for a rest before you jump again, If you practice, you can increase the number of limes you jumpers without resting. Before you do rope jumping, you must   _  .
find a good player try whether the rope will be right for you stop to rest for an hour try whether the rope will be strong enough
Question: Every student can learn rope jumping. You can jump alone or with your classmate. You can also help turn a long rope for many others to jump over, one at a time. If you jump alone, you will need a short rope and it will be just enough for your height. Try ropes of different lengths until you find a right one for your size.  A rope should be turned slowly. It must also be turned high enough to let you jump freely and safely. Turning the rope freely and safely needs careful timing. In rope jumping, timing means turning the rope slowly enough for you to jump over at the right time without its striking your feet. When you jump rope, your heart beats faster and your face has a healthy color1. But if you jump too many times at first, you will get fired. You must learn when to stop for a rest before you jump again, If you practice, you can increase the number of limes you jumpers without resting. Before you do rope jumping, you must   _  .
A. find a good player
B. try whether the rope will be right for you
C. stop to rest for an hour
D. try whether the rope will be strong enough
Answer: