Read the following paragraphs and answer the question.
     Women are retreating from marriage as they go into the workplace. That’s partly because, for a woman, being both employed and married is tough in Asia. Women there are the primary caregivers for husbands, children and, often, for ageing parents; and even when in full-time employment, they are expected to continue to play this role. This is true elsewhere in the world, but the burden that Asian women carry is particularly heavy. Japanese women, who typically work 40 hours a week in the office, then do, on average, another 30 hours of housework.

What contributes to the decline of marriage in Asian countries?（）