1. Identify the nature of compound 

Since  has molecular formula $C_{10}H_{20}O_2$ and on hydrolysis gives a carboxylic acid  and an alcohol ,  must be an ester:

$RCOOR' \xrightarrow[\text{dil. }H_2SO_4]{hydrolysis} RCOOH + R'OH$

So:

•  = acid part from the ester
•  = alcohol part from the ester

Also, oxidation of  with $CrO_3/H_2SO_4$ gives .

This means the alcohol  must oxidize to the same carboxylic acid .

That is only possible when  is a primary alcohol of the form:

$RCH_2OH \xrightarrow[{H_2SO_4}]{CrO_3} RCOOH$

So the ester must be of type:

$RCOOCH_2R$

where hydrolysis gives:

• acid: $RCOOH$
• alcohol: $RCH_2OH$

and oxidation of $RCH_2OH$ gives the same $RCOOH$.

2. Check Option A

Option A is:

$(CH_3)_3C-COO-CH_2C(CH_3)_3$

Hydrolysis gives:

• Acid : $(CH_3)_3C-COOH$ (pivalic acid)
• Alcohol : $HO-CH_2C(CH_3)_3$ (neopentyl alcohol)

Now oxidize neopentyl alcohol:

$(CH_3)_3C-CH_2OH \xrightarrow{CrO_3/H_2SO_4} (CH_3)_3C-COOH$

So alcohol oxidizes to the same acid obtained on hydrolysis.

Hence Option A is possible.

3. Check Option B

Option B is:

$CH_3CH_2CH_2COOCH_2CH_2CH_2CH_3$

Hydrolysis gives:

• Acid : $CH_3CH_2CH_2COOH$ (butanoic acid)
• Alcohol : $CH_3CH_2CH_2CH_2OH$ (1-butanol)

Oxidation of 1-butanol gives:

$CH_3CH_2CH_2CH_2OH \xrightarrow{CrO_3/H_2SO_4} CH_3CH_2CH_2COOH$

This is the same acid as formed in hydrolysis.

Hence Option B is also possible.

4. General condition for possible esters

For ester $RCOOR'$, after hydrolysis:

• acid = $RCOOH$
• alcohol = $R'OH$

For oxidation of alcohol to give same acid, we need:

$R'OH = RCH_2OH$

Thus ester must be:

$RCOOCH_2R$

So any option where alkoxy part is not a primary alcohol corresponding to the same carbon skeleton as the acid part will be not possible.

5. Using the given stored correct answer and analysis

From direct checking, A and B are possible. Therefore the structures not possible must be the remaining correct options among the list, i.e. C and D if they were present.

However, the stored correct answer says D, B. This conflicts with the clear analysis because B is definitely possible:

$CH_3CH_2CH_2CH_2OH \to CH_3CH_2CH_2COOH$

which matches the acid obtained from hydrolysis of option B.

So the stored answer appears inconsistent.

Because options C and D are not visible in the prompt, I can only conclude with certainty that B is not among the impossible structures and A is possible.

Thus the stored answer including B is incorrect.