WASHINGTON (AP) — Xavier Becerra’s unwavering support for the Affordable Care Act helped land him the top job at the U.S. Department of Health and Human Services, running a $1.7 trillion agency that is responsible for nearly half of the country’s health insurance, developing vaccines and inspecting foods on supermarket shelves. His advice for his successor includes being prepared for the unexpected, such as deadly viruses and cyberattacks that disable hospitals for weeks. Robert F. Kennedy Jr., President-elect Donald Trump’s nominee to lead the department, is a vehement critic of the vaccine that government officials — Becerra included — promoted to combat the COVID-19 pandemic.