Ruby, Gary, Sam, and Anna work in a software development firm. Who among them is responsible for the talent management function of the firm's HR department?

a$.$ Sam, who develops career planning programs for the firm's employees

b$.$ Anna, who creates employee selection tools such as skills assessment tests

c$.$ Gary, who ensures the availability of qualified individuals to fill vacant job positions in the firm

d$.$ Ruby, who develops job descriptions and job specifications for vacant job positions