Frequency is the amt of times you would repeat a workout. good rule of thumb would be creating a balanced program where the reps (or frequency) balances out w/ the difficulty. ur welcome love :)
The correct answer is A.
Q: But how, also, why?
A:

Formula to the solution should explain everything. ^
Answer:
B- A deep cut in a surface.
Explanation:
One definition of a Channel is " a groove or furrow. " , which most aligns with answer B.