With reference to nucleic acids, consider the following statements: 1. DNA is a double-stranded molecule while RNA is generally a single-stranded molecule. 2. The sugar in DNA is deoxyribose, whereas in RNA it is ribose. 3. DNA uses the nitrogenous base Uracil (U) instead of Thymine (T), which is found in RNA. Which of the statements given above is/are correct?

1. A1 and 2 only
2. B1, 2 and 3
3. C2 only
4. D1 and 3 only