Choose the correct HTML code for below structure :A. <table><tr><th>Languages</th><th>Proficiency</th></tr><tr><td>C++</td><td>Java</td><td>Javascript</td></tr><tr><td>Beginner</th><td>Intermediate</td><td>Advanced</td></tr></table>B. <table><tr><td>Languages</td><td>C++</td><td>Java</td><td>Javascript</td></tr><tr><td>Proficiency</td><td>Beginner</th><td>Intermediate</td><td>Advanced</td></tr></table>​C. <table><th><td>Languages</td><td>C++</td><td>Java</td><td>Javascript</td></th><tr><td>Proficiency</td><td>Beginner</th><td>Intermediate</td><td>Advanced</td></tr></table>D. <table><tr><th>Languages</th><td>C++</td><td>Java</td><td>Javascript</td></tr><tr><th>Proficiency</th><td>Beginner</th><td>Intermediate</td><td>Advanced</td></tr></table>

The correct HTML code for the given structure is option A.

Here's why:

In HTML, a table is created using the <table> tag. Each row is created with the <tr> tag. Inside these row elements, you can use the <th> tag to create header cells and the <td> tag to create data cells.

Option A correctly uses these tags to create a table with two rows. The first row has two headers: "Languages" and "Proficiency". The second row has three data cells: "C++", "Java", and "Javascript". The third row has three data cells: "Beginner", "Intermediate", and "Advanced".

The other options either use the wrong tags or arrange them incorrectly. For example, option B and D use <td> tags where they should use <th> tags, and option C incorrectly nests a <td> tag inside a <th> tag.

The correct HTML code for the given structure is D.

Here's why:

In HTML, a table is created using the <table> tag. Each row is created with the <tr> tag. Inside these row elements, you can use <th> to define a header cell, and <td> to define a data cell.

Option D correctly uses these tags to create a table with two rows. The first row has a header cell "Languages" followed by data cells for each language (C++, Java, Javascript). The second row has a header cell "Proficiency" followed by data cells for each proficiency level (Beginner, Intermediate, Advanced).

The other options either use the wrong tags or arrange them incorrectly. For example, option A uses <th> for the proficiency levels, which is incorrect because these are not headers. Option B and C incorrectly place the "Languages" and "Proficiency" cells, and also use incorrect tags.