Concept:Factorisation by grouping terms to find the common binomial factor.Explanation:Rearrange the expression so like terms are grouped:mn−nq−n2+mq=mn−n2+mq−nqGroup the first pair and the last pair:(mn−n2)+(mq−nq)Take out the common factor from each group:n(m−n)+q(m−n)Now factor out the common binomial (m−n):(m−n)(n+q)Answer:The other factor is (n+q), which is option C.