Each item in this section has a sentence with three underlined parts labelled (a), (b) and (c). Read each sentence to find out whether there is any error in any underlined part and indicate your response on the Answer Sheet against the corresponding letter i.e., (a), (b), (c). If you find no error, your response should be indicated as (d).
`("The visitor's to the zoo are requested,")/((a)) ("in the interest of all concerned,")/((b)) ("not to carry sticks, stones or food inside and not to tease animals.")/((c)) ("No error.")/((d))`