Final answer:
A double bond consists of one sigma (σ) bond and one pi (π) bond, so the correct answer is A) One.
Step-by-step explanation:
In a chemical bond, a double bond is made up of one sigma (σ) bond and one pi (π) bond. A sigma bond is a single covalent bond that is formed from the direct overlap of atomic orbitals, allowing for two electrons to be shared between atoms. In a double bond, while the sigma bond is the first to form and allows for end-to-end overlap, the pi bond is characterized by a side-to-side overlap and does not exist without the sigma bond. Therefore, the correct answer to how many sigma bonds are in a double bond is A) One.