The correct answer is d. handcrafted.
Here's why:
Preserved implies that the pottery items are being kept safe from decay or deterioration, which doesn't necessarily relate to the process of creating them.
Followed doesn't make sense in this context, as it suggests following something or someone.
Built is more associated with constructing structures or objects, not creating pottery.
Handcrafted accurately describes the process of creating pottery by hand, which is likely the case in a Pottery & Arts Studio.
 

All of our pottery iteams are                    in our Pottery & Arts Studio
a.preserved               b.followed
c.built                        d.handicrafted

Trong câu này, từ phù hợp để điền vào chỗ trống là "handicrafted" (thủ công), vì câu nói về các sản phẩm gốm sứ được tạo ra bằng tay trong studio nghệ thuật và gốm sứ.

All of our pottery iteams are                    in our Pottery & Arts Studio
a.preserved               b.followed
c.built                        d.handicrafted