Directions (Qs. 19 to 27): In the following items, each passage consists of six sentences. The first and sixth sentences are given in the beginning as S1 and S6. The middle four sentences in each have been jumbled up. These are labelled P, Q, R and S. Find out the proper sequence of the four sentences and mark your answer accordingly on the Answer-sheet.
21. S1: Plants need carbon for building the tissue of their bodies.
S6: Thus through a complex process called photosynthesis, plants receive their requirements from soil and Sun.
P: The breaking up of carbon dioxide into its components requires energy, which they derive from the Sun.
Q: Plants' other needs of nutrients are derived from the soil and water through their roots.
R: They derive this carbon from carbon dioxide, absorb the carbon and discharge oxygen into the air for animals to breathe.
The proper sequence should be
- AQSPR
- BRSPQ
- CSQRP
- DPRQS
Explanation
The flow is R (derive carbon from CO2) → S (breaking CO2 needs energy from the Sun) → P (energy derived from the Sun) → Q (other nutrients from soil and water); the official key marks B.