Correct Answer: C

Rationale: The term 'flexible' accurately describes the type of tube used in the given context. A 'solid' tube would not have been suitable for navigating a curved pipe as it is not pliable. 'Rigid' implies stiffness and inflexibility, making it unsuitable for the task. 'Perforated' means pierced with holes, which is unrelated to the plumber's task of opening up a curved pipe.

Correct Answer: D

Rationale: In the United States, drivers drive on the 'right' side of the road. This is the standard practice in the country. Choice A 'Rite' is incorrect as it is a misspelling of 'Right.' Choice B 'Left' is incorrect as driving on the left side is common in countries like the UK, not the US. Choice C 'Off-side' is incorrect as it is not a standard term used to describe the side of the road where people drive in the US.

Correct Answer: A

Rationale: The correct answer is 'Chronology,' which specifically means the arrangement of events in the order of their occurrence. 'Notation' refers to a system of symbols or signs used to represent information. 'Documentation' is the process of recording information, while 'Helicon' does not relate to the description of events.

Correct Answer: B

Rationale: The correct answer is 'Fontanel.' Fontanels are the soft spots on a newborn's head where the skull bones have not yet fused together, allowing for some flexibility during birth and rapid brain growth in early infancy. 'Fistula' is a medical term for an abnormal connection between two body parts. 'Follicle' refers to a small cavity in the skin from which hair grows. 'Fissure' is a narrow opening or crack, not related to the soft spots on a newborn's head.

Correct Answer: B

Rationale: The correct answer is 'B: Residual.' In the given sentence, 'residual' is used to describe something that is left or remaining. 'Residual' fits the context perfectly as it aligns with the definition of what remains. The other choices are incorrect: A) 'Resident' refers to a person living in a specific place, C) 'Resistance' is the act of opposing or withstanding something, and D) 'Resin' is a sticky substance produced by plants.