Answer:
d) H2SO3
Step-by-step explanation:
The Arrhenius theory defines an acid as a substance that releases H+ ions in aqueous solution. Also among the options listed, H2SO3 is the only acid present, you can tell due to the fact that it's leading with an H. However, not all acids lead with an H, like Acetic Acid CH3COOH (Choo Choo Acid helps me remember it) ends with an H.
Here's a description of each compound.
a) NH2CH3: Methylamine, a weak base.
b) CH3CH3: Ethane, a hydrocarbon and not an acid or base.
c) KOH: Potassium hydroxide, a strong base.
d) H2SO3: Sulfurous acid, a weak acid.
e) LiOH: Lithium hydroxide, a strong base.
Hope this helps!