4d, 5p, 5f and 6p orbitals are arranged in the order of decreasing energy. The correct option is

(2) 6p > 5f > 5p > 4d

(3) 6p > 5f > 4d > 5p

(4) 5f > 6p > 4d > 5p

answer : from all above options the correct answer is “(1) 5f > 6p > 5p > 4d“

explanation of correct answer : Smaller the value of (n + 1) for a particular subshell , smaller will be its energy. if the value of n+1 is small in quantity than it’s energy also will be small.

If for two subshells, the (n + 1) value is the same then the subshell having higher value of n will have higher energy it means if the n+1 is higher than the energy of it’s subshell also will be higher , let’s calculate the n+1 value and on the based of n+1 value the energy will be decided.