Which antenatal client is most suitable for transfer to a postpartum unit when the nurse-to-client ratio increases?

The most suitable client for transfer to a postpartum unit based on the provided options would be a woman at 12 weeks' gestation with vaginal bleeding. This choice is correct because while vaginal bleeding during the first trimester can be concerning, it does not typically require the same level of immediate, high-risk monitoring and intervention as the conditions presented by the other clients in the options.

The woman at 10 weeks' gestation with nausea may be experiencing typical pregnancy-related nausea, commonly referred to as morning sickness. While it's uncomfortable, it usually does not necessitate postpartum-level care.

The woman at 26 weeks' gestation with hypertension presents a potentially serious situation. Hypertension during pregnancy can lead to complications such as preeclampsia, which requires careful monitoring and management.

The woman at 36 weeks' gestation in active labor is also in a critical phase of pregnancy. Active labor requires close observation and management, as she is preparing for delivery and may need immediate postpartum care following labor and delivery.

In summary, the woman with vaginal bleeding is the best candidate for transfer given her condition is less urgent compared to the other clients, allowing resources to be allocated effectively in a situation where nurse-to-client ratios are increasing.