Many inexperienced triathletes are surprised to (94) ______hard it can be to switch from swimming to cycling to running, and how tired their muscles can suddenly feel.
Many inexperienced triathletes are surprised to (94) ______hard it can be to switch from swimming to cycling to running, and how tired their muscles can suddenly feel.
A. find what
B. find out why
C. find out how
D. find how