**Core Concept**
The girl's presentation with generalized swelling, grade 3 proteinuria, and the presence of hyaline and fatty casts suggests nephrotic syndrome. This condition is characterized by excessive loss of protein in the urine, leading to hypoalbuminemia, edema, and hyperlipidemia. Nephrotic syndrome can be caused by various underlying pathologies, including minimal change disease (MCD), focal segmental glomerulosclerosis (FSGS), and membranous nephropathy.

**Why the Correct Answer is Right**
The correct answer states that there will be no IgG deposits or C3 deposition on renal biopsy. This is a characteristic feature of minimal change disease (MCD), which is the most common cause of nephrotic syndrome in children. MCD is characterized by the absence of immune deposits, including IgG and C3, on immunofluorescence staining. The condition is thought to result from a breakdown in the glomerular filtration barrier, leading to the loss of large molecules, including proteins.

**Why Each Wrong Option is Incorrect**
**Option B:** This option is incorrect because C3 deposition is not typically associated with minimal change disease. C3 deposition is more commonly seen in conditions such as membranoproliferative glomerulonephritis (MPGN) and membranous nephropathy.

**Option C:** This option is incorrect because IgA nephropathy is characterized by the deposition of IgA antibodies in the glomeruli, which is not consistent with the presentation of this patient. IgA nephropathy typically presents with hematuria, particularly after an upper respiratory tract infection.

**Option D:** This option is incorrect because Alport's syndrome is a genetic disorder characterized by the deposition of type IV collagen in the glomeruli, leading to chronic kidney disease. Alport's syndrome typically presents with hematuria, hearing loss, and eye abnormalities, which are not consistent with this patient's presentation.

**Clinical Pearl / High-Yield Fact**
In patients with nephrotic syndrome, it is essential to perform a renal biopsy to differentiate between the various underlying causes. The absence of immune deposits on immunofluorescence staining is a key feature of minimal change disease.

**✓ Correct Answer: A. No IgG deposits or C3 deposition on renal biopsy**