Explanation:

- Let's consider the weight of C as 100 units.

- B's weight is 30% more than C, making it 130 units (100 + 30% of 100).

- A's weight is 20% more than B, making it 156 units (130 + 20% of 130).

- Now, calculate by how much percent A's weight is more than C’s:

$$(\frac{156-100}{100})\times 100=56\mathrm{\%}$$

- Therefore, A's weight is 56% more than C's weight.

Option 2 - 56 is indeed the correct choice.