Answer: Yes, they do.
Explanation: Neutrons and protons are made up of smaller subatomic particles. When neutons and protons get get close to each other they convert particles and bond together. This occurance is called The Strong Force.
Well, you don't need enzymes (biological catalysts) if you're willing to wait a century or two to digest a burger.
Without catalysts, complex reactions like digestion would take too long and the organism could not extract energy from the nutrients it eats in a practical time frame.
In addition, speed is everything in the biological world.
Some reactions and their speed relative to other organisms reactions determines who survives and who doesn't, among other aspects of life.
If a plant is slow to photosynthesize and grow in a habitat high in competition for sunlight real estate, other autotrophs will surely take over.
Nails are made up of iron not of phosphorus and barium.
As both phosphorous and barium are relatively weaker than iron ,phosphorus breaks easily and barium is also fairly weak. Iron nails are already also not that strong, but their weight and strength are sufficient.
So the nails are made up of iron.
good sir it seems your answer appears to be B