From which tab in word can you add an excel object, such as a worksheet or a chart?
a. layout
b. design
c. insert
d. home

That would be C, Insert.

Layout is mainly for formatting issues, such as spacing, etc.
Design is similar, but it deals more with appearance.
Home just includes a bunch of basic settings that include font and lists.
Insert is where you go to insert special objects, such as charts or worksheets.

Hope this helps!