**Core Concept**
The question is testing knowledge of the healthcare system's approach to caring for patients with disabilities or handicaps. This involves understanding the role of various healthcare professionals and institutions in providing comprehensive care to this vulnerable population.

**Why the Correct Answer is Right**
The correct answer is **Social Worker**. Social workers play a crucial role in providing care and support to handicapped patients by assessing their needs, developing care plans, and linking them with community resources. They work closely with other healthcare professionals, such as doctors, nurses, and therapists, to ensure that patients receive holistic care. Social workers also advocate for patients' rights and interests, helping to address social and environmental barriers that may impact their quality of life.

**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because while doctors are essential in diagnosing and treating handicapped patients, they are not primarily responsible for providing ongoing care and support.

**Option B:** This option is incorrect because while nurses play a vital role in patient care, they may not have the specialized training or expertise to provide comprehensive support to handicapped patients.

**Option C:** This option is incorrect because while therapists, such as occupational or physical therapists, may work with handicapped patients to develop skills and abilities, they are not primarily responsible for providing overall care and support.

**Clinical Pearl / High-Yield Fact**
It's essential to remember that handicapped patients often require a multidisciplinary approach to care, involving not only healthcare professionals but also family members, caregivers, and community resources.

**Correct Answer: D. Social Worker**