Step 1: Go through each claim like a checklist. Conventional tillage disturbs the topsoil every season, which speeds up decomposition and loss of organic matter, matching (A).
Step 2: It also leaves soil bare between crops, so moisture evaporates faster, matching (B).
Step 3: It breaks up natural soil aggregates and crumbles structure with each pass, matching (D).
Step 4: Compaction from repeated tillage and machine traffic builds up gradually and is a long-term risk, not a short-term one, so the wording in (C) does not match the accepted drawback.
Step 5: Keeping only the statements that match known drawbacks leaves (A), (B) and (D).
\[oxed{ ext{(A), (B) and (D) only}}\]