Step 1: Ask what each feed is known for
Green fodder: moisture, vitamins. Dry fodder: fibre. Concentrates: protein and energy. Hay: dried roughage.
Step 2: Pick the vitamin match
The vitamin job goes to green fodder, which is option (1).
Step 3: Why dry feeds lose out
Sun drying and storage break down vitamins, so dry fodder and hay (options 2 and 4) are poor vitamin sources.
Step 4: Why concentrates lose out
Oil cakes, grains and bran are valued for protein and energy, so option (3) does not fit. This is a standard fact in livestock and fodder topics, so it is worth remembering for the exam. Reading the passage first and then checking each option against it avoids careless mistakes.
Final Answer:
Green fodder is the vitamin source, so the answer is option (1).
\[ \boxed{\text{Option (1)}} \]
