Because A, B, C and D are not necessary technical features, a+ and b+ lack oneness.
For example,
1. A bicycle comprises wheels, a seat cushion, a handle and a driving device, and is characterized in that it is connected with the seat cushion. . . . . .
2. A bicycle, comprising wheels, a seat cushion, a handle and a driving device, characterized in that the bicycle is connected with the wheels. . . . . .
Bicycles include wheels, seat cushions, handlebars and driving devices, which are well known and not necessary technical features, so the improvement on seat cushions and wheels is not unitary.
I suggest you apply separately.
Add a classic case from "Review Procedure".
Case 1
Claim 1: An airbag for a vehicle includes a shield for folding the airbag, and a retainer that can be locked to the shield. In the locked state, the shield and the holder define a receiving area.
Claim 2: The vehicle airbag according to claim 1, characterized in that the receiving area is formed by a pit formed on the shield.
Claim 3: An airbag for a vehicle includes a shield for folding the airbag and a holder that can be locked to the shield, and the holder has a rectangular bottom plate.
Claim 4: The airbag for a vehicle as claimed in claim 3, characterized in that the retainer has a buffer portion which can be elastically deformed at its side pointing to the shield.
case analysis
Treatment processes that can be adopted:
(1) It is determined that the vehicle airbags in two independent claims 1 and 3 have the same technical features "shield" and "retainer".
(2) According to the examiner's own knowledge in the field of airbags, the independent claim 1 and 3 do not belong to obvious non-oneness, and should be searched and examined.
As far as this case is concerned, because the subject matter defined in Claim 1 ~ 4 is the same, the technical scheme is relatively simple, and the technical fields and search scope of both are basically the same, it is judged as a whole that the search and review of Claim 1 ~ 4 will not increase too much workload, and the search can be carried out at the same time.
(3) After searching, it is found that independent claims 1 and 3 are not creative, while dependent claims 2 and 4 are creative. That is to say, the same technical features "shield" and "fixer" are not specific technical features, but the features in Claims 2 and 4 that make the present invention contribute to the prior art are different.
(4) Write a notice of examination opinions, pointing out that claims 1 and 3 are not creative. Considering the possibility that the applicant will upgrade Claims 2 and 4 to independent claims when revising, the notice also points out that there is a single defect between Claims 2 and 4 in order to save procedures.
(5) Continue the examination after the applicant replies and/or modifies the application documents.