The unique characteristic of the amino acid cysteine is
a high level of acidity
its ability to form hydrogen bonds
its ability to form disulfide bridges a second amino group

C. the last one

Explanation:

the answer is the

> b takes place in the gas phase in an isothermal tubular reactor. the feed is one mole of a per one mole of c, an inert. the entering temperature and pressure are 427°c and 10 atm, respectively. the gas constant r = 0.08206 atm · l/mol · k.