In the following question, a sentence has been given in Direct speech. Out of the four alternatives suggested, select the one which best expresses the same sentence in Indirect (Reported) speech. 'He said, "I saw a snake here."'

Introduction / Context:
This Direct and Indirect speech question tests your understanding of tense changes, place word changes and proper structure when reporting a past statement. The original sentence is 'He said, "I saw a snake here."' You must convert it into reported speech without quotation marks, following the usual grammar rules applied when the reporting verb is in the past tense.

Given Data / Assumptions:
- Direct speech: 'He said, "I saw a snake here."'
- Reporting verb: 'said' (simple past).
- Reported clause: 'I saw a snake here.'
- The speaker is 'he'; 'I' in the quote refers back to 'he' in reported speech.

Concept / Approach:
When converting from Direct to Indirect speech and the reporting verb is in the past tense, we usually backshift the tense in the reported clause: simple past becomes past perfect ('saw' becomes 'had seen'). Pronouns are changed according to the speaker and context: 'I' (the speaker) becomes 'he'. Place words like 'here' usually change to 'there' when reporting later from a different location. We introduce the reported clause with 'that'. Putting this together gives 'He said that he had seen a snake there.'

Step-by-Step Solution:
Step 1: Change the pronoun: 'I' becomes 'he' because the speaker is 'he'. Step 2: Backshift the tense: the original 'saw' (simple past) becomes 'had seen' (past perfect) after the past reporting verb 'said'. Step 3: Change the place adverb 'here' to 'there' to reflect indirect reporting from a different place. Step 4: Introduce the reported clause with 'that': 'He said that he had seen a snake there.'

Verification / Alternative check:
Option (a) is 'He said that he had seen a snake there.', which matches all the necessary changes of pronoun, tense and place word, and keeps the meaning that at some earlier time he saw a snake at that place. Option (b) keeps both the original tense 'saw' and the word 'here', which is not the standard transformation in reported speech when the context has changed. Option (c) changes only 'here' to 'there' but does not backshift the tense. Option (d) backshifts the tense correctly but drops the place word entirely, which is an unnecessary loss of information.

Why Other Options Are Wrong:
Option (b) 'He said that he saw a snake here.' is wrong because it uses 'here', which is inappropriate once the sentence is detached from the original speech situation, and it does not change the tense from simple past to past perfect. Option (c) 'He said that he saw a snake there.' corrects the place word but still keeps simple past 'saw', which does not follow the usual backshifting rule under a past reporting verb. Option (d) 'He said that he had seen a snake.' correctly uses past perfect but omits 'here/there', losing the location information present in the original sentence.

Common Pitfalls:
A common error is to apply only one rule and forget the others; for example, some students change 'here' to 'there' but forget to backshift the tense, or they change the tense but overlook pronoun changes. When converting to indirect speech, form a checklist in your mind: 1) adjust pronouns, 2) backshift tense if needed, 3) change time and place words (now/then, here/there, today/that day) and 4) remove quotation marks, introducing the clause with 'that' when appropriate.

Final Answer:
The correct reported speech form is 'He said that he had seen a snake there.'