The correct option is D NO IMPROVEMENT
Option D: The sentence is grammatically correct, because 'need' when followed by the verb 'to be', must be followed by a past participle 'painted'. (A participle is a form of a verb that expresses a tense in a sentence). The sentence means that the table requires to be painted by someone.
Hence the sentence needs no improvement and option D is correct.
Option A: 'Paint' is a noun, when it replaces the underlined word, it changes the meaning of the sentence. The sentence now means that the table needs to turn into paint, or be paint. This sentence has no coherent meaning, hence A is incorrect.
Option B: 'Painting' when added, also changes the meaning of the sentence, making it sound illogical. The sentence now means that the table has to perform the action of painting. Inanimate objects cannot perform such an action. Hence B is also incorrect.
Option C: 'Having paint' changes the tense of the sentence to present continuous and the sentence sounds chaotic: The table needs to be having paint. 'To be' is usually not followed by a present participle 'having'. Hence C is incorrect.