The side effects associated with antihistamines are multiple choice hypertension and urinary incontinence sedation and xerostomia agitation and insomnia narcolepsy and bradycardia

Sedation and xerostomia are the side effects of antihistamines

Explanation:

Taking antihistamines make a person feel sleepy or experiencing drowsiness or sedation. It is advised not to drive cars when you having this medication because it decreases your response rate to the stimuli in your surroundings. Another side effects of using antihistamine is the feeling of dry mouth also known as xerostomia which is characterize by hypofunction of salivary glands thus producing decreased salivary flow.  

regulation of gene expression. gene expression can be regulated by various cellular processes with the aim to control the amount and nature of the expressed genes. these regulatory proteins bind to dna and send signals that indirectly control the rate of gene expression

explanation:

the answer is c.mitochondria. glad to .