Tartar is

Correct Answer: D

Rationale: The correct answer is D: Bacterial deposits. Tartar is primarily composed of hardened bacterial plaque that accumulates on teeth when plaque is not adequately removed through brushing and flossing. This process is known as calcification. Tartar buildup can lead to various dental issues. Clenching the teeth (A) refers to a different dental behavior, gum inflammation (B) is a result of poor oral hygiene but not directly related to tartar, and bad-smelling breath (C) can be caused by various factors, including poor oral hygiene, but is not the primary definition of tartar.

Correct Answer: A

Rationale: The correct answer is A: Chronic renal failure. Chronic renal failure is a disorder of the urinary system where the kidneys are unable to effectively filter waste products from the blood. This leads to a buildup of waste products and toxins in the body, causing various symptoms and complications. Rationale: 1. Chronic renal failure specifically refers to the long-term and progressive decline in kidney function, leading to impaired waste filtration. 2. Urinary tract infection (B) is an infection in any part of the urinary system, not a disorder of kidney filtration. 3. Urinary incontinence (C) is the inability to control urination, not related to kidney filtration. 4. End-stage renal disease (D) is the final stage of chronic renal failure where the kidneys have lost most of their function, making it a severe consequence of chronic renal failure, not the disorder itself.

Correct Answer: C

Rationale: The correct answer is C (36 to 48 hours) because the ovum, once released during ovulation, has a lifespan of approximately 24 hours. Sperm can survive in the female reproductive tract for up to 5 days, but if fertilization does not occur within 36 to 48 hours after ovulation, the ovum will degenerate and not be viable for fertilization. Choices A, B, and D are incorrect because they do not align with the known lifespan of the ovum and the window of fertilization opportunity.

Correct Answer: C

Rationale: The correct answer is C: Swelling in the ankles. In congestive heart failure, the heart's inability to pump effectively leads to fluid buildup in the body, causing swelling in the ankles (edema). Decreased urination (A) is a symptom of kidney dysfunction in heart failure. Weight loss (B) is not typical in heart failure due to fluid retention. Decreased pulse (D) is not a common sign of heart failure; in fact, heart failure can lead to a rapid or irregular pulse.

Correct Answer: C

Rationale: The correct answer is C: Phantom sensation. Phantom sensation refers to the warmth, itching, or tingling felt in a body part that has been amputated. This phenomenon occurs due to the brain still receiving signals from the nerves that used to be connected to the now missing body part. Osteoporosis (A) is a condition characterized by weakening of bones, not related to sensations in amputated limbs. Bursitis (B) is inflammation of the bursae, not associated with phantom sensations. Osteoarthritis (D) is a degenerative joint disease, not related to sensations in amputated limbs.