Answer: A.

Explanation:
For angle y in a right triangle ,the trigonometric ratio of cos y is given by :-

Given: The side adjacent to angle L= 5 units
The side opposite to angle L = 12 units
Let h be the hypotenuse, then using Pythagoras in the given right triangle, we get
Thus, hypotenuse = 13 units
Now, the trigonometric ratio for cos L is given by :-

Hence, the value of cos L =