Question

Select the CORRECT option that shows the match between spectral bands and the factors affecting the spectral signature of vegetation at the leaf level.

Spectral bands	Factors affecting the spectral signature of vegetation at the leaf level
(P) Green	(i) Water content in the leaf
(Q) Red	(ii) Internal structure of the leaf
(R) Near Infrared	(iii) Absorption from chlorophyll
(S) Shortwave Infrared	(iv) Reflectance from chlorophyll

• A. (P)-(iv), (Q)-(iii), (R)-(ii) and (S)-(i)
• B. (P)-(iii), (Q)-(iv), (R)-(ii) and (S)-(i)
• C. (P)-(iv), (Q)-(iii), (R)-(i) and (S)-(ii)
• D. (P)-(iii), (Q)-(iv), (R)-(i) and (S)-(ii)

Hint:

Remember the leaf-level rule of thumb: SWIR relates to leaf water content, NIR relates to internal leaf structure, and the visible bands relate to chlorophyll, with red being absorbed strongly and green reflected relatively more.

Answer 1

The Correct Option is A

Step 1: Fix the one association you are most sure of first.
The shortwave infrared (S) band is universally associated with water absorption features of the leaf, so $(S)$-$(i)$ must hold.
Step 2: Eliminate options that violate this.
Option (C) pairs $(S)$-$(ii)$ and option (D) pairs $(S)$-$(ii)$ as well, both wrong, so options (C) and (D) are eliminated, leaving only options (A) and (B).
Step 3: Distinguish (A) from (B) using the Green/Red pair.
Option (A) has $(P)$ Green $\to (iv)$ reflectance from chlorophyll and $(Q)$ Red $\to (iii)$ absorption from chlorophyll. Option (B) swaps these.
Step 4: Decide which pairing is physically correct.
Chlorophyll absorbs red light strongly (hence low red reflectance, an absorption feature) and absorbs green light only weakly (hence the green reflectance peak that makes leaves look green). This matches option (A)'s pairing, not option (B)'s.
Step 5: Conclude.
Option (A) is the only one consistent with both the SWIR-water rule and the correct Green/Red chlorophyll behavior. \[ \boxed{\text{Option (A)}} \]