Q1. (2) had planned will be used.
Q2. (3) fewer: not many is used for Countable Nouns. Hence, no fewer is the right usage.
Q3. (3) outstretched (Adj.) : spread out as far as possible stretch out (Phr. V.) : to lie down in order to relax or sleep.
Here, outstretched in the ditch is the right usage
Q4. (1) presently (Adv.) : now ; currently; at the time you are speaking by this time : a particular allotted time.
Here, presently is the right usage.
Q5. (1) cut down on (Phrasal Verb) : to reduce
get rid of (Phrasal Verb) : to make yourself free of something that is annoying or that you do not want or do not want to do
Here, cut down on is the right usage.
Q6. 6. (3) irritates (Verb.) : to annoy somebody, especially by something you continuously do or by something that continuously happens
incessant (Adj.) : never stopping ; constant
annoys (Verb.) : to make some body slightly angry ; irritates
Here, irritates is the right usage.
Q7. (1) Not only _____ but also are Correlative Conjunctions.
Sentence structure is as follows :
Not only + Aux. verb + Subject
Not only + did + they
Hence, Not only did they go is the right usage.
Q8. (3) fill the air by their sweet notes is the right usage.
Q9. (3) power (Noun) : strength or influence in a particular area of activity
giant (Noun) : a very large and powerful organisation
Here, power is the right usage.
Q10. (4) No improvement