Mutations in ubiquitin lead to malfunction of what organelle in ALS that leads to buildup of mis-folded proteins?

a. mitochondria

b. microtubules

c. vacuoles

d. proteasome

Mitochondria.

Explanation:

Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disorder in which the neuron died due to mutation in superoxide dismutase 1 gene. This disease is also known as Lou Gehrig's disease.

Mitochondria structure is disorganized in ALS. The ubiquitin protein mutation leads to the malfunctioning of mitochondria and misfolded proteins are made in the mitochondria.

Thus, the correct answer is option (a).