【C3】A．generationsB．descentsC．causesD．origins

A．selectionsB．collectionsC．sourcesD．origins

He has found a lot of reasons to explain his failure.A.effectsB.resultsC.causesD.bases

What were the effects of the decision she had made？A.reasonsB.resultsC.causesD.bases

【C7】A．providesB．witnessesC．causesD．holds

【C12】A．basesB．factorsC．causesD．fractions

Which of the following theories is NOT about the origin of language？A．Divine-origin theory