Which is not a fibrous joint:
First costochondral joint is a hyaline cailage joint (synchondrosis or syscendrosis), which is a type of primary cailagenous joint. Sutures of skull, Inferior tibifibular joint (syndesmosis), denotalveolar joint (gomphosis) are examples of fibrous joint.
Gomphoses
Cranial sutures
First costochondral joint
Inferior tibiofibular joint