Significance of the study in a research work briefly states all the following except

Correct Answer: C

Rationale: The significance of a study explains its value and impact. 'Relationship between two variables,' is correct as the exception because it's part of hypotheses or findings, not significance, per research guides (e.g., Creswell). 'The overall impact...,' and 'Potential benefits...,' highlight societal and individual value. 'Possible usefulness and contribution,' addresses practical implications. Significance focuses on why the study matters, not specific variable links, making C the odd one out, aligned with research structure.

Correct Answer: B

Rationale: Cardiac reserve is the difference between maximum cardiac output (CO) during exercise and resting CO. Resting CO = 84 × 0.06 = 5 L/min; exercise CO = 13 L/min. Reserve = 13 - 5 = 8 L/min. '8 L/min,' is correct, per cardiovascular physiology (e.g., Berne & Levy). Choice A is exercise CO, not reserve. Choice C and D misalign. B's calculation fits, making it the answer.

Correct Answer: B

Rationale: Iodine is essential for thyroid hormone synthesis (T3 and T4), regulating metabolism. 'Iodine,' is correct, per endocrinology texts like Williams' Textbook of Endocrinology, where iodine deficiency disrupts metabolic rate. 'Iron,' is in hemoglobin, not thyroid-specific. 'Calcium,' affects bones and signaling, not metabolism via thyroid. 'Magnesium,' supports enzymatic function, not thyroid-related metabolism. Iodine's incorporation into thyroxine, directly influencing basal metabolic rate, makes B the precise answer, critical to thyroid physiology.

Correct Answer: C

Rationale: Oxytocin, from the posterior pituitary, triggers milk ejection by contracting myoepithelial cells in the breast. 'Oxytocin,' is correct, per physiology texts like Costanzo, distinct from milk production. 'Progesterone,' supports pregnancy, not ejection. 'Prolactin,' stimulates milk synthesis. 'Oestrogen,' aids breast development. Oxytocin's specific let-down reflex role makes C the accurate answer, critical in lactation.

Correct Answer: C

Rationale: Vitamin C (ascorbic acid) prevents scurvy by aiding collagen synthesis, essential for connective tissue. 'Vitamin C,' is correct, per nutrition texts like Shils, reversing symptoms like bleeding gums. 'Vitamin A,' supports vision. 'Vitamin B,' is a group, none specific to scurvy. 'Vitamin D,' aids bone health. Vitamin C's historical link to scurvy prevention, notably in sailors, makes C the accurate answer.