Final answer:
The standard deduction is increased for taxpayers who are blind or deaf at year-end.
Step-by-step explanation:
The true statement among the given options is A. The standard deduction is increased for taxpayers who are blind or deaf at year-end. This means that taxpayers who are blind or deaf may qualify for a higher standard deduction when calculating their taxable income. For example, in the year 2020, the standard deduction for a single taxpayer without any additional qualifications is $12,400, while for a blind or deaf taxpayer, it is increased to $13,650.