Passage

Eight railway stations A, B, C, D, E, F, G, and H are connected either by two-way passages or one-way passages. One-way passages are from C to A, E to G, B to F, D to H, G to C, E to C, and H to G. Two-way passages are between A and E, G and B, F and D, and E and D.
QUESTION

CSAT

Easy

Reasoning

Prelims 2017

While travelling from C to H, which one of the following stations must be passed through?

Select an option to attempt

Explanation

One-way passages:

CAC \rightarrow A EGE \rightarrow G BFB \rightarrow F DHD \rightarrow H GCG \rightarrow C ECE \rightarrow C HGH \rightarrow G Two-way passages:

AEA \leftrightarrow E GBG \leftrightarrow B FDF \leftrightarrow D EDE \leftrightarrow D Starting at station C, the only direct one-way passage is CAC \rightarrow A. From A, you can travel to E via the two-way passage AEA \leftrightarrow E. From E, you have two options:

EGE \rightarrow G (one-way) EDE \leftrightarrow D (two-way)

If you choose EGE \rightarrow G, you can then travel to C via the one-way passage GBFDHG \leftrightarrow B \rightarrow F \leftrightarrow D \rightarrow H. Further, another viable option is to take the two-way passage EDE \leftrightarrow D, leading you to station D. From D, you can proceed to H via the one-way passage DHD \rightarrow H.

Thus, the mandatory station to pass through when traveling from C to H is E.

Therefore, the correct answer is E.

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