Which of the following sentences is grammatically CORRECT？A．China will further intensify b

Which of the following sentences is grammatically CORRECT？

A．China will further intensify bilateral, multilateral and regional economic cooperation in a long run.

B．My company is a big firm, there nearby is a big market for software in my city.

C．We will never stop less they give up at first.

D．Despite of his opposition, she worked in her own way and started her preparations.

请帮忙给出正确答案和分析，谢谢！