Identify the segment in the sentence which contains a grammatical error.
Her health has being steadily improving since she started practising yoga.

Correct option is D

The correct meaning of the highlighted idiom "boils down to" is "sums up to."

• Boils down to: This idiom means to be the most important or fundamental aspect of something; to reduce something to its essential element.
• Example: The debate on climate change ultimately boils down to the need for sustainable practices.

Similar Idioms:

1. Comes down to: This phrase also means that the main issue or point can be summarized or reduced to something essential.
   • Example: The success of the project comes down to good management.
2. Amounts to: Refers to the essential or most significant part of something after considering all factors.
   • Example: All his efforts ultimately amounted to nothing when the plan failed.