A
1, 4, 3, 2
B
4, 1, 2, 3
C
1, 4, 2, 3
D
4, 1, 3, 2
Correct answer: (c) 1, 4, 2, 3
Explanation
- A
1, 4, 3, 2
1, 4, 3, 2. Puts radio before ultraviolet.
- B
4, 1, 2, 3
4, 1, 2, 3. Starts with X-rays; gamma is higher frequency.
- C
1, 4, 2, 3
1, 4, 2, 3. Gamma → X-rays → ultraviolet → radio (decreasing frequency).
- D
4, 1, 3, 2
4, 1, 3, 2. X-rays first; radio before UV.
Summary. Official key is (c) 1, 4, 2, 3. Gamma, X-rays, UV, radio. Also note: c = fλ — Higher f, shorter λ; Gamma — Highest f in this set; Radio — Lowest f; Visible — Between UV and IR; not listed.