IMO BFrom the sentence 2 things -Advice and Speculation- as indicated by the word
'both' given by oil minister helped heating oil prices surge to record levels last week
(A) that inventory of heating oil be marked up to meet an impending severe winter as well as the speculation that a major unit may close for a long time due to a major accident, helped heating oil prices surge to record levels last week --
Incorrect both used with as well as (B that inventory of heating oil be marked up to meet an impending severe winter and the speculation that a major unit may close for a long time due to a major accident, helped heating oil prices surge to record levels last week--
Correct usage of both© to mark up the inventory of heating oil to meet an impending severe winter along with the speculation that a major unit may close for a long time due to a major accident, helped heating oil prices surge to record levels last week
Incorrect usage of both with 'along with'
(D) to mark up the inventory of heating oil to meet an impending severe winter as well as the speculation of a major unit probably closing for a long time due to a major accident, helped heating oil prices surge to record levels last week
Same as A(E) to mark up the inventory of heating oil to meet an impending severe winter coinciding with the speculation that a major unit may probably close for a long time due to a major accident, helped heating oil prices surge to record levels last week --
Incorrect usage of both Please post OA and OE.