So option )D is the answer sense it is pointing directly at the negative charge!
Answer:
The correct answer is "α-helices only use intrachain hydrogen bonds and β-sheets can use either intrachain or interchain hydrogen bonds".
Explanation:
Hydrogen bonding are essential forces for the formation of the secondary structures of proteins. The alpha helix is a coiled secondary structure that is stabilized only by intrachain hydrogen bonds, which are formed between the NH and CO groups of the main chain. On the other hand, β-sheets can use either intrachain or interchain hydrogen bonds for its stabilization. Adjacent chains in β-sheets can run either in the same or opposite directions, which are stabilized by interchain hydrogen bonds.

If every oxygen ion is combined with aluminum ion, has a charge of -2, The charge of each aluminium ion must be -3.
Uncharged Aluminum atom must need to lose it's electrons,in order to form the bond with oxygen which has vacant orbitals
ion.
atom that has a positive or negative charge because it lost or gained one or more electrons
chemical bond
the attractive force that holds atoms or ions together
ionic bond
a chemical bond in which one atom loses an electron and the other atom gains electrons to form ions
chemical formula
a combination of chemical symbols and numbers to represent a substance
covalent bond
bond formed by the sharing of electrons between atoms
Thanks
I believe that would be C6H6, Benzene.
Hope it helps!