344. Pick up the correct statement from the following
A. the contour lines having the same elevation cannot unite and continue as one line
B. a contour can not end abruptly, but must ultimately close itself not necessarily within the limits of map.
C. the direction of steepest slope at a point on a contour is at right angles to the contour
D. all the above.

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345.  Assertion : The plane horizontal at one point does not precisely coincide with that through any other point. Reason : The directions of plumb lines suspended at different points in a survey are not strictly parallel.
A. Both A and R are true and R is the correct explanation of A
B. Both A and R are true but R is not a correct explanation of A
C. A is true but R is false
D. A is false but R is true.

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346.  Assertion : In extensive survey operations in any area, it is always better to use the information of geodetic surveys available in the area.Reason : It saves the engineer or surveyor a great deal of work in providing his own control points and also enables him to obtain most useful checks at various stages of his work.
A. Both A and R are true and R is the correct explanation of A
B. Both A and R are true but R is not a correct explanation of A
C. A is true but R is false
D. A is false but R is true.

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347.  Assertion : The working from the whole to the part presents the accumulation of error. Reason : The error tends to magnify itself very quickly.
A. Both A and R are true and R is the correct explanation of A
B. Both A and R are true but R is not a correct explanation of A
C. A is true but R is false
D. A is false but R is true.

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348.  Assertion : An accurate basic control is required to be established for surveying an area of large extent. Reason : Large errors are prevented and minor ones are controlled and localised.
A. Both A and R are true and R is the correct explanation of A
B. Both A and R are true but R is not a correct explanation of A
C. A is true but R is false
D. A is false but R is true.

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349.  Assertion : While making adjustment of survey instruments, they should be placed on firm ground Reason : Instability of the instrument makes it impossible to adjust it satisfactorily.
A. Both A and R are true and R is the correct explanation of A
B. Both A and R are true but R is not a correct explanation of A
C. A is true but R is false
D. A is false but R is true.

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350.  Assertion : The prisms of large deflection are not normally found in surveying instruments. Reason : The light of different colours is differently deflected.
A. Both A and R are true and R is the correct explanation of A
B. Both A and R are true but R is not a correct explanation of A
C. A is true but R is false
D. A is false but R is true.

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