Mandarin
Mandarin, although the tree is not small. The kumquat has small fruits, usually made into marmalade.
the English of calamansi is "small citrus fruit"
Citrus paradisi.
The scientific name would be Citrus paradisi x reticulata.
The mandarin is a type of citrus fruit and it is also the name given to a type of porcelain.
A lemon or a grapefruit.
lemon
Citrus limon
The pomelo.
Citrus sinensis
Gooseberry is an edible fruit. They can be eaten or used in pies.
As it's name, It's a FRUIT.