单项选择题
The line with the most stretch is（）.
A.manila B.nylon C.polypropylene D.dacron
单项选择题 The latch of a safety hook（）.
单项选择题 The knot used to join two lines or two large hawsers for towing is called a（）.
单项选择题 The knot used to join two lines of different diameter is a（）.
