Which statement is true about the bisque stage?

• A. The clay has not been fired yet
• B. The clay is fully vitrified
• C. The clay has been glazed and fired again
• D. The clay has been fired once and is porous before glazing

Answer: (D)

The key idea is what happens after the first firing in ceramics. Bisque firing is the initial firing that turns clay into ceramic material, but it does not vitrify the clay. After this first firing, the piece is porous—it can drink up water and glaze because its pores are still open. That porous, unfused state is what makes glaze application possible; the glaze sits in and around the pores and then fuses during a subsequent firing.

So the statement describing the bisque stage as having been fired once and still being porous before glazing is the accurate one. The other descriptions don’t fit: unfired clay hasn’t undergone any firing yet; fully vitrified clay has become glassy and non-porous, which isn’t the bisque stage; and glazing followed by another firing refers to the glaze firing after bisque, not to bisque itself.