What particular rights does the legislation concerning pregnant employees ensure?

The correct choice highlights that legislation regarding pregnant employees is primarily concerned with ensuring their health and well-being during pregnancy. This encompasses various rights and protections related to their working conditions, which could include provisions for maternity health and safety assessments, adjustments in their job role or environment to accommodate any pregnancy-related health issues, and protection from discrimination based on pregnancy.

While other options discuss aspects related to maternity leave and pay, they do not directly address the core focus of legislative measures aimed at caring for pregnant employees during their actual pregnancy. Instead, these measures are specifically designed to support the physical and psychological health of employees throughout their pregnancy, reflecting a commitment to safeguarding their rights and welfare in the workplace.