Consider the following four statements (A-D) and select the correct option stating which ones are true (T) and which ones are False (F).
(A) Vertical distribution of different species occupying different levels in a community is called stratification.
(B) Net primary productivity minus respiration losses is the gross primary productivity.
(C) Rate of biomass production is called decompostion.
(D) Annual net primary productivity of oceans is 55 billion tons.

Options

A. `{:(" "(A),(B),(C),(D)),((1)" "F,T,F,T):}`
B. `{:(" "(A),(B),(C),(D)),((2)" "T,F,T,F):}`
C. `{:(" "(A),(B),(C),(D)),((3)" "T,F,F,T):}`
D. `{:(" "(A),(B),(C),(D)),((4)" "F,T,F,F):}`

Answer

To solve the question, we need to evaluate each statement (A-D) to determine if it is true (T) or false (F).

### Step-by-Step Solution:

1. **Statement A**: "Vertical distribution of different species occupying different levels in a community is called stratification."
- This statement is **True (T)**. Stratification refers to the layering of different species in a community, often seen in ecosystems like forests where different species occupy different heights.

2. **Statement B**: "Net primary productivity minus respiration losses is the gross primary productivity."
- This statement is **False (F)**. Gross primary productivity (GPP) is the total amount of carbon fixed by photosynthesis, while net primary productivity (NPP) is GPP minus the respiration losses. Therefore, the statement incorrectly defines GPP.

3. **Statement C**: "Rate of biomass production is called decomposition."
- This statement is **False (F)**. The rate of biomass production is referred to as productivity, not decomposition. Decomposition is the process by which organic substances are broken down into simpler organic or inorganic matter.

4. **Statement D**: "Annual net primary productivity of oceans is 55 billion tons."
- This statement is **True (T)**. The annual net primary productivity of oceans is indeed estimated to be around 55 billion tons, reflecting the productivity of marine ecosystems.

### Summary of Statements:
- A: True (T)
- B: False (F)
- C: False (F)
- D: True (T)

### Final Answer:
The correct option is: A (T), B (F), C (F), D (T).

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