And the traditional preference for boys sometimes leads to selective abortion, causing worries over the imbalance of gender ratio.

想要男孩的传统偏好导致许多人选择堕胎，这就造成了大家担心男女比例的失衡的问题。

youdao

Countermeasures: fair use, temperance drug use, develop the risk-benefit ratio, low residue and selective pesticides.

对策：公道用药，节制用药，研制高效低毒，低残留并有选择性的农药。

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Selective suitable conditions such as the ratio of reactions, different catalyst and the addition of dehydrater etc are presented. The result which is the yield of product is 82.5%.

选择了合适的原料配比、催化剂、脱水剂用量等反应条件，反应所得到的丙酮酸乙酯收率为82.5%；

youdao

There, selective poaching of males has led to a dramatic skew in the sex ratio.

NPR: Lifting the Ivory Ban Called Premature