【正确答案】 A

【答案解析】[解析] 画线词的原形restrict为动词，意为“限制”，与A项的原形limit(限制)为同义词；例：The teacher limited his students to 500 words for their compositions.老师把学生的作文限制在500字以内。B项的原形allow意为“允许”；例：Their teacher allowed them three days for the assignment.老师给他们三天时间完成作业。C项的原形stop意为“阻止”；例：The policemen stopped the fight.警察制止了这场斗殴。D项的原形keep意为“保持”；例：I kept it all the time to remind me of you.我一直保存着它，使自己想着你。