Filgrastim is the drug used in the treatment of anti-cancer therapy-induced neutropenia.
Filgrastim injection is used to treat neutropenia (low white blood cells) that is caused by cancer medicines. It is a synthetic (man-made) form of a substance that is naturally produced in your body called a colony-stimulating factor. Filgrastim helps the bone marrow to make new white blood cells.
Filgrastim is a recombinant human G-CSF(granulocyte-colony stimulating factor), that stimulates CFU-G(colony-forming unit- granulocyte) to increase neutrophil production. It is administered subcutaneously or by slow intravenous infusion. It is indicated in:

The treatment of severe neutropenia after autologous hematopoietic stem cell transplantation and high-dose cancer chemotherapy.
The treatment of severe congenital neutropenias.
The treatment of neutropenia of patients with AIDS receiving zidovudine.
Important adverse reactions include bone pain, local skin reaction, and cutaneous necrotizing vasculitis.

Other options:

Option A: Romiplostim is a thrombopoietin receptor agonist. It is used in the management of immune thrombocytopenic purpura(ITP).
Option B: Oprelvekin is a recombinant human IL-11. It stimulates hematopoiesis. It is used in the treatment of thrombocytopenia due to non-myeloid malignancies. Important adverse effects are fluid retention, tachycardia, palpitation, edema, and shortness of breath.
Option D: Recombinant human erythropoietin including epoetin alfa is used in the treatment of anemias associated with surgery, chronic kidney disease, AIDS, cancer chemotherapy, prematurity, and certain chronic inflammatory conditions.

Reference: KD Tripathi Edition8 Page no 936

Drugs Affecting Cells of Blood