Simple molecules and covalent bonds — practice question

Which row explains how single covalent bonds form in methane?

• Aatoms share a pair of electrons; both atoms gain a noble gas electronic structure
• Batoms share a pair of electrons; both atoms have the same number of electrons in their outer shell
• Celectrons are transferred from one atom to another; both atoms gain a noble gas electronic structure
• Delectrons are transferred from one atom to another; both atoms have the same number of electrons in their outer shell