Answer:
The correct answer is - n and l.
Step-by-step explanation:
The size of an orbital is determined by the principal number of shell which is represented by n. The larger the energy level (n) bigger the size of the orbital. N can be any integer value: 1, 2, 3 . . . . and so on.
l represents the angular momentum or subshell number provides the overall shape of an orbital in this subshell only integer values between 0 and n-1 are permitted.
Thus, n & l are two quantum numbers that determine the energy level of an orbital in a multielectron atom.