Reaction of Red Hot Carbon with Steam Produces Hydrogen Gas

Reaction of red hot carbon with steam produces hydrogen gas as shown in equation 1 below. The carbon monoxide that is produced in equation 1 can react further with steam to produce more hydrogen as shown in equation 2. Why are these two reactions undesirable methods for producing hydrogen gas?
(1) C (s) + H₂O (g) →H₂ (g) + CO (g) (2) CO (g) + H₂O (g) →H₂ (g) + CO₂ (g)

A) The carbon monoxide produced in equation 1 is a poisonous gas.
B) The carbon dioxide produced in equation 2 is a greenhouse gas.
C) The carbon dioxide produced in equation 2 is a poisonous gas.
D) Elemental carbon is very expensive.
E) Both answers a and b are correct.